NAME
URL::Normalize - Normalize/optimize URLs.
VERSION
Version 0.16
SYNOPSIS
use URL::Normalize;
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/display?lang=en&article=fred',
);
# ...or
my $Normalizer = URL::Normalize->new(
url => '/display?lang=en&article=fred',
base => 'http://www.example.com',
);
# Get a normalized URL back
$Normalizer->do_all(); # Perform all the normalizations available
print $Normalizer->get_url();
DESCRIPTION
This is NOT a perfect solution. If you normalize a URL using all the
methods in this module, there is a high probability that the URL will
"stop working". This is merely a helper module for those of you who
wants to either normalize a URL using only a few of the safer methods,
and/or for those of you who wants to generate a unique "ID" from any
given URL.
When writing a web crawler, for example, it's always very costly to
check if a URL has been fetched/seen when you have millions or billions
of URLs in a sort of database. This module can help you create a unique
"ID", which you then can use as a key in a key/value-store; the key is
the normalized URL, whereas all the URLs that converts to the normalized
URL are part of the value (normally an array or hash);
'http://www.example.com/' = {
'http://www.example.com:80/' => 1,
'http://www.example.com/index.html' => 1,
'http://www.example.com/?' => 1,
}
Above, all the URLs inside the hash normalizes to the key if you run
these methods:
* `make_canonical()'
* `remove_directory_index()'
* `remove_empty_query()'
CONSTRUCTORS
new( %opts )
Constructs a new URL::Normalize object. Takes a hash as input argument;
my $Normalizer = URL::Normalize->new(
url => '/foobar.html', # required
base => 'http://www.example.com/', # optional
);
METHODS
get_URI()
Returns the `URI' object representing the current state of the URL.
get_url()
Returns the current URL.
get_base()
Returns the current base.
make_canonical()
Just a shortcut for URI::URL->new()->canonical()->as_string(), and
involves the following steps (at least):
* Converts the scheme and host to lower case.
* Capitalizes letters in escape sequences.
* Decodes percent-encoded octets of unreserved characters.
* Removes the default port (port 80 for http).
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/%7Eusername/',
);
$Normalize->make_canonical();
print $Normalize->get_url(); # http://www.example.com/~username/
remove_dot_segments()
The segments ".." and "." will be removed from the URL according to the
algorithm described in RFC 3986.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/../a/b/../c/./d.html',
);
$Normalize->remove_dot_segments();
print $Normalize->get_url(); # http://www.example.com/a/c/d.html
remove_directory_index()
Removes well-known directory indexes, eg. "index.html", "default.asp"
etc.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/index.cgi?foo=/',
);
$Normalizer->remove_directory_index();
print $Normalizer->get_url(); # http://www.example.com/?foo=/
You are free to modify the global `$DIRECTORY_INDEX_REGEXPS' arrayref to
your own fitting:
$URL::Normalize::DIRECTORY_INDEX_REGEXPS = [ ... ];
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/index.cgi?foo=/',
);
$Normalizer->remove_directory_index();
print $Normalizer->get_url(); # whatever
sort_query_parameters()
Sorts the query parameters alphabetically.
Uppercased parameters will be lower cased during sorting only, and if
there are multiple values for a parameter, the key/value-pairs will be
sorted as well.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/?b=2&c=3&a=0&A=1',
);
$Normalizer->sort_query_parameters();
print $Normalizer->get_url(); # http://www.example.com/?a=0&A=1&b=2&c=3
remove_duplicate_query_parameters()
Removes duplicate query parameters, ie. where the key/value combination
is identical with another key/value combination.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/?a=1&a=2&b=4&a=1&c=4',
);
$Normalizer->remove_duplicate_query_parameters();
print $Normalizer->get_url(); # http://www.example.com/?a=1&a=2&b=3&c=4
remove_empty_query_parameters()
Removes empty query parameters, ie. where there are keys with no value.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/?a=1&b=&c=3',
);
$Normalize->remove_empty_query_parameters();
print $Normalizer->get_url(); # http://www.example.com/?a=1&c=3
remove_empty_query()
Removes empty query from the URL.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/foo?',
);
$Normalizer->remove_empty_query();
print $Normalize->get_url(); # http://www.example.com/foo
remove_fragment()
Removes fragments from the URL.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/bar.html#section1',
);
$Normalizer->remove_fragment();
print $Normalizer->get_url(); # http://www.example.com/bar.html
remove_duplicate_slashes()
Remove duplicate slashes from the URL.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/foo//bar.html',
);
$Normalizer->remove_duplicate_slashes();
print $Normalizer->get_url(); # http://www.example.com/foo/bar.html
remove_hostname_prefix()
Removes 'www' followed by a potential number before the actual hostname.
Example:
my $Normalizer = URL::Normalize->new(
url => 'http://www.example.com/',
);
$Normalizer->remove_hostname_prefix();
print $Normalizer->get_url(); # http://example.com/
do_all()
Performs all of the normalization methods mentioned above.
PERFORMANCE
There's probably possible to improve the performance of this module
considerably, but as premature optimization is evil, I'll wait until the
functionality and API is stable.
On my MacBook Pro (2.66GHz i7, 8GB RAM) running Perl 5.14.2, I'm able to
run the do_all() method on more than 1,100 URLs per second. This is just
a number, as the performance depends on the complexity of the URL.
SEE ALSO
* URI
* URI::URL
* URI::QueryParam
* RFC 3986: Uniform Resource Indentifier
* Wikipedia: URL normalization
AUTHOR
Tore Aursand, `'
BUGS
Please report any bugs or feature requests to the web interface at
https://github.com/toreau/url-normalize/issues/new.
SUPPORT
You can find documentation for this module with the perldoc command.
perldoc URL::Normalize
You can also look for information at:
* github (report bugs here)
https://github.com/toreau/url-normalize/issues
* AnnoCPAN: Annotated CPAN documentation
http://annocpan.org/dist/URL-Normalize
* CPAN Ratings
http://cpanratings.perl.org/d/URL-Normalize
* Search CPAN
http://search.cpan.org/dist/URL-Normalize/
LICENSE AND COPYRIGHT
Copyright 2012-2013 Tore Aursand.
This program is free software; you can redistribute it and/or modify it
under the terms of the the Artistic License (2.0). You may obtain a copy
of the full license at:
http://www.perlfoundation.org/artistic_license_2_0
Any use, modification, and distribution of the Standard or Modified
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your Modified Version complies with the requirements of this license.
This license does not grant you the right to use any trademark, service
mark, tradename, or logo of the Copyright Holder.
This license includes the non-exclusive, worldwide, free-of-charge
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otherwise transfer the Package with respect to any patent claims
licensable by the Copyright Holder that are necessarily infringed by the
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